Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10145 (IL-8)
 23,849 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recent studies have demonstrated a relationship between cytokines and gastric acid secretion. However, details of the mechanism underlying that relationship have not been elucidated. For this study, an in vivo experiment was undertaken to investigate the possibility that IL-8 would be involved in the mechanism of gastric acid secretion. Gastric lumen-perfused rats were prepared and the stomachs were perfused with a saline solution. The effluent was collected at 15-min intervals and assayed for titratable acid against 0.01 M NaOH. IL-8 (200 ng/rat) given intravenously did not influence basal acid output in rats. However, when IL-8 was administered by injection during continuous tetragastrin infusion (4 microg/kg/hr) acid output increased significantly (P < 0.01). The acid output during the first hour following IL-8 injection was 43.6% higher than prior to the injection. Acid output during the second hour was lower than during the first hour. However, successive injection of IL-8 again increased tetragastrin-stimulated acid output by 23.4% (P < 0.05). IL-8 injection did not change histamine-stimulated acid output. The results indicate that IL-8 has the effect of enhancing gastrin-stimulated acid secretion and might have an important role in the pathophysiology of gastric acid secretion in vivo.
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PMID:Interleukin-8 enhances tetragastrin-stimulated acid secretion in vivo. 979 Apr 71

In pharmaceutical research G protein-coupled receptors (GPCR) emerged as a superfamily of prominent drug targets. Extensive protein sequence analyses on GPCRs revealed a common protein topology consisting of a membrane-spanning seven-helix bundle, which is believed to accommodate the binding site for low-molecular weight ligands. Enormous efforts are undertaken to generate GPCR structural models by means of molecular modelling, since these have already been shown to aid the process of lead structure finding and optimisation in that they provide atomistic models for structure-based drug design approaches. One of the most critical steps in modelling the transmembrane domains of GPCRs is the assignment of the putative transmembrane sequence stretches from multiple protein sequence alignment analyses. This study focuses on the comparative evaluation of protein sequence analysis tools, such as periodicity analyses, multiple sequence analyses or directional helix descriptors, especially developed for modelling the 7TM domains of GPCRs. In this context we will demonstrate that from application of different methods contradictory results can be obtained for the identification of the putative transmembrane sequence stretches of peptide-binding GPCRs, as exemplified with a comprehensive protein sequence analysis study based on the most prominent members of that receptor class (angiotensin II, CCK/gastrin, interleukin 8, endothelin, etc.).
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PMID:Molecular modelling studies on G protein-coupled receptors: from sequence to structure? 1007 69

In order to investigate the effects of early enteral feeding on the gut after burn, 21 cases (mean burn area 45%) were randomly divided into early feeding group (EF group) and delayed feeding group (DF group). The results showed that the levels of plasma endotoxin and MDA in EF group were much lower on PBD 4, 8, 14 than those of DF group (P < 0.05-0.01), and plasma SOD was much lower in DF group on PBD 4, 8 (P < 0.01). The contents of serum gastrin and plasma motilin were obviously increased, and TNF IL-8 much lower in EF group at most time points (P < 0.05-0.01). Therefore, it seems that the early enteral feeding can decrease the level of plasma endotoxin in blood, reduce reperfusion injury of the gut, and blunt the chain reaction of "endotoxin-inflammatory mediator-gut mucosa injury."
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PMID:[A clinical study of early enteral feeding to protect the gut function in burned patients]. 1045 11

Rosacea is a common condition of unknown etiology usually accompanied by gastrointestinal symptoms and favorably responding to the treatment with antibiotics. This study was designed to examine the prevalence of gastric Helicobacter pylori (Hp) infection verified by 13C-UTB-test, CLO, Hp culture and serology (IgG) in patients with rosacea. Gastroduodenoscopy was combined with pentagastrin secretory test and antral and fundic biopsy samples were taken for histological evaluation (the Sydney system). Blood samples were also taken for the determination of plasma gastrin using RIA and plasma interleukin (IL)-8 and tumor necrosis factor alpha (TNFalpha) using ELISA. This study was performed in 60 patients, 31-72 year old, with visible papules and pustules associated with erythema and flushing on the face and on 60 age- and gender-matched patients without any skin diseases but with similar as in rosacea gastrointestinal symptoms but without endoscopic changes in gastroduodenal mucosa (non-ulcer dyspepsia - NUD). The Hp prevalence in rosacea patients was about 88 % as compared to 65% in control NUD patients. Among rosacea patients, 67% were cytotoxin associated gene A (CagA) positive, while in NUD patients only 32% were CagA positive. Rosacea patients showed gastritis with activity of about 2.1 in antrum and 0.9 in the corpus of the stomach while those with NUD only mild gastritis with activity of approximately 1.0) confined to the antrum only. Following initial examination, typical 1 wk anti-Hp therapy including omeprazole (20 mg bd.), clarithromycin (500 mg bd.) and metronidazol (500 mg bd.) was carried out. After eradication, 51 out of 53 treated rosacea patients became Hp negative. Within 2-4 weeks, the symptoms of rosacea disappeared in 51 patients, markedly declined in 1 and remained unchanged in 1 other subject. A dramatic reduction in activity of gastritis (to 0.3 in antrum and to 0.1 in corpus) was observed. Basal plasma gastrin decreased from 48 +/- 5 pM before to 17+/-3 pM after eradication, while pentagastrin-induced maximal (MAO) declined, respectively, from about 16.6 +/- 4.2 to 8.5 +/- 1.8 mmol/h. Plasma TNFalpha and IL-8 were reduced after the therapy by 72% and 65%, respectively. We conclude that: 1) Rosacea is a disorder with various gastrointestinal symptoms closely related to gastritis, especially involving the antrum mucosa, with Hp expressing cagA in the majority of cases and elevated plasma levels of TNFalpha and IL-8; 2) The eradication of Hp leads to a dramatic improvement of symptoms of rosacea and reduction in related gastrointestinal symptoms, gastritis, hypergastrinemia and gastric acid secretion; and 3) Rosacea could be considered as one of the major extragastric symptoms of Hp infection probably mediated by Hp-related cytotoxins and cytokines.
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PMID:Helicobacter pylori and its eradication in rosacea. 1069 58

Numerous epidemiological studies demonstrated the association between Helicobacter pylori (H. pylori) infection and gastric cancer but the mechanism of the involvement of H. pylori in gastric cancerogenesis remains virtually unknown. This study was designed to determine the seropositivity of H. pylori and cytotoxin associated gene A (CagA), serum gastrin and gastric lumen gastrin levels under basal conditions and following stimulation with histamine in gastric cancer patients and controls. 100 gastric cancer patients aging from 21 to 60 years and 300 gender- and age-adjusted controls hospitalized with non-ulcer dyspepsia (NUD) entered this study. 13C-Urea Breath Test (UBT), serum immunoglobulin (IgG) antibodies to H. pylori and CagA were used to assess the H. pylori infection and serum levels of IL-1beta, IL-8 and TNFalpha were measured by enzyme-linked immunosorbent assay (ELISA) to evaluate the degree of gastric inflammation by H. pylori . Gastrin-17 mRNA and gastrin receptors (CCK(B)) mRNA expression in gastric mucosal samples taken by biopsy from the macroscopically intact fundic and antral mucosa as well as from the gastric tumor was determined using RT-PCR. The overall H. pylori seropositivity in gastric cancer patients at age 21-60 years was about 92%, compared, respectively, to 68%, in controls. A summary odds ratio (OR) for gastric cancer in H. pylori infected patients was about 5.0 . The H. pylori CagA seropositivity in gastric cancer patients was about 58.5% compared to 32.4% in controls, giving the summary OR for gastric cancer in CagA positive patients about 8.0. The prevalence of H. pylori- and H. pylori CagA-seropositivity was significantly higher in cancers than in controls, irrespective of the histology of gastric tumor (intestinal, diffuse or mixed type). Median IL-1beta and IL-8 reached significantly higher values in gastric cancer patients (9.31 and 30.8 pg/ml) than in controls (0.21 and 3.12, respectively). In contrast, median serum gastrin in cancers (as total group) was several folds higher (62.6 pM) than in controls (19.3 pM). Also median luminal gastrin concentration in gastric cancer patients was many folds higher (310 pM) than in controls (20 pM). This study shows for the first time that cancer patients are capable of releasing large amounts of gastrin into the gastric lumen to increase luminal hormone concentration to the level that was recently reported to stimulate the growth of H. pylori. There was no any correlation between plasma gastrin levels and gastric luminal concentration of gastrin suggesting that: 1) luminal gastrin originates from different source than plasma hormone, most probably from the cancer cells, 2) cancer cells are capable of expressing gastrin and releasing it mainly into the gastric juice and 3) the gastric cancer cells are equipped with gastrin-specific (CCK(B)) receptor so they exhibit the self-growth promoting activity in autocrine fashion. This notion is supported by direct detection of gastrin mRNA and gastrin receptor (CCK(B)-receptors) mRNA using RT-PCR in cancer tissue. To our knowledge this is the first study showing an important role of gastrin as self-stimulant of cancer cells in patients infected with H. pylori. Basal and histamine maximally stimulated acid outputs were significantly lower in gastric cancer patients than in controls despite of enhanced gastrin release, particularly in cancer patients and this might reflect the mucosal inflammatory changes (increased serum levels of proinflammtory interleukins - IL-1beta and IL-8), that are known to increase gastrin release. We conclude that: 1) H. pylori infected patients, particularly those showing CagA-seropositivity, are at greatly increased risk of development of gastric cancer, 2) H. pylori-infected cancer patients produce significantly more IL-1beta and IL-8 that might reflect an H. (ABSTRACT TRUNCATED)
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PMID:Role of gastrin in gastric cancerogenesis in Helicobacter pylori infected humans. 1069 65

In the present study we ascertained whether cagA positive and negative H. pylori strains release water soluble products that can influence the production of gastric mucosal cytokines and endocrine (gastrin) or exocrine (pepsinogen C) secretion in 23 H. pylori positive and 19 H. pylori negative patients. Antral biopsies were obtained to classify inflammation, activity, atrophy, intestinal metaplasia and H. pylori density grade. The cagA gene was identified by means of the polymerase chain reaction (PCR) in H. pylori positive colonies after culture of mucosal samples. Three antral biopsies from each patient were incubated with (1.) Water extracts from cagA positive, (2.) Water extracts from cagA negative strains or (3.) H2O (control) at 37 degrees C in a CO2 incubator for 24 hrs. Gastrin, pepsinogen C, IL-1 beta, IL-8, GMCSF, and TNF alpha were measured in the supernatants and mucosal homogenates. H. pylori infection was significantly associated with an increased antral inflammation and activity (chi 2 = 21.7, p < 0.001 and chi 2 = 42.0, p < 0.001), and increased mucosal levels of IL-1 beta, IL-8 and TNF alpha. Water extracts from cagA positive strains enhanced the release of PGC in mucosal biopsy supernatants (p < 0.05) when patients were considered overall and the release of TNF alpha (p < 0.05) when only patients with duodenal ulcer were considered. Water extracts from cagA negative strains stimulated gastrin secretion (p < 0.05). None of the remaining cytokines were influenced by H. pylori water extracts. In conclusion, pepsinogen C and TNF alpha can be induced by cagA positive water extracts and may contribute to damage the gastric and duodenal mucosa. Our findings indicate that in patients with H. pylori infection the increase of the mucosal levels of IL-1 beta and IL-8 does not depend on H. pylori water soluble products, but probably depends on the entire bacterium.
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PMID:Different effects of H. pylori water extracts on cytokines, pepsinogen C and gastrin mucosal release in patients with or without duodenal ulcer. 1132 91

The pathophysiology of hypergastrinemia in H. pylori infection has been largely investigated and different reports clearly show that the infected antrum has a marked inflammatory response with a suggestive local production of cytokines. Notwithstanding, a few data are available on the circulating levels of cytokines and gastrin in the asymptomatic people carrying H. pylori infection. Thus, aim of the study was to evaluate circulating proinflammatory cytokines [Interleukin (IL)-8, Interleukin (IL)-10, Interferon (IFN)-gamma, and Tumor Necrosis Factor (TNF)-alpha] and gastrin levels in H. pylori positive asymptomatic subjects vs. H. pylori negative ones. To this end, thirty healthy volunteers with no digestive symptoms or systemic disease were enrolled and H. pylori infection was identified by a 13C-urea breath test. Plasma levels of gastrin were determined using the RIA kit whereas IL-8, TNF-alpha, IL-10, and IFN-gamma levels in serum were measured with a solid-phase ELISA. Fifteen infected people showed significantly higher gastrin and TNF-alpha levels than uninfected subjects. On the contrary, IL-8 levels were significantly higher in the uninfected subjects than in H. pylori positive ones (P < 0.0422). IFN-gamma and IL-10 circulating levels were not affected by H. pylori presence, being not significantly different in the two groups.
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PMID:Circulating cytokines and gastrin levels in asymptomatic subjects infected by Helicobacter pylori (H. pylori). 1132 45

Colorectal cancers (CRCs) are one of the most common forms of cancer in Poland and one of the leading causes of death. The tumors have been attributed to genetic, dietary, and other environmental factors, but recently growth factors such as gastrin have also been implicated in the carcinogenesis. The relationship between plasma amidated and nonamidated gastrin in CRCs is controversial. This study was designed (1) to determine the plasma levels of progastrin and amidated gastrin in 50 CRC patients before and 3-6 months after removal of the tumor, (2) to determine the tumor concentrations of these gastrin peptides and the level of expression for gastrin mRNA and gastrin/CCK(B) receptor mRNA, (3) to examine the expression of cyclooxygenase COX-1 and COX-2 mRNA in CRC tissue, and (4) to compare the prevalence of Hp and its cytotoxic protein, CagA, and cytokines (TNFalpha, IL-1beta, and IL-8) in CRCs, before and after removal of tumor. It was found that the CRC, its resection margin, and the plasma contained severalfold higher levels of progastrin than of amidated gastrins and that the removal of the CRC tumor resulted in a marked reduction in plasma progastrin level without a significant alteration in plasma levels of amidated gastrins. Both gastrin and CCK(B)-R mRNA were detected in the cancer tissue and resection margin by RT-PCR, and similarly, COX-1 and COX-2 mRNA were expressed in these tissues of most CRCs. The seroprevalence of Hp, especially that expressing CagA, and levels of IL-1beta, but not other cytokines, were significantly higher in CRC patients than in 100 age-, gender-, and profession-matched controls and did not change significantly about 3-6 months after tumor resection. We conclude that (1) the CRC and its margin contain large amounts of progastrin and show gene expression of gastrin, CCK(B)-R, and COX-2; (2) removal of the CRC markedly reduces the plasma concentrations of progastrin; (3) the Hp infection rate is higher in CRC, and this may contribute to colorectal cancerogenesis via enhancement of progastrin and gastrin release; and (4) plasma progastrin concentrations might serve as a biomarker of CRC.
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PMID:Progastrin and cyclooxygenase-2 in colorectal cancer. 1235 42

H. pylori colonisation of the stomach causes the recruitment of the inflammatory cells by the adherence of the bacteria with the epithelium and the release of factors of virulence either to the contact (oipA or other soluble factors) or in the cell by translocation (CagA). Such contact triggers interleukin 8 expression in the epithelial cell and attracts lymphocytes and monocytes into the chorion. Bacterial lipopolysaccharide and urease support the activation of these inflammatory cells. The lymphocytes produce pro-inflammatory cytokines, which direct the immune response towards the Th1 pathway. The variability of the inflammatory response depends on hereditary factors of the host such as the interleukin 1 genotypes, which determine the level of the pro-inflammatory cytokine expression, and of bacterial factors such as the cag pathogenicity island, the lipopolysaccharide and the vacuolating toxin, vacA. The mucosal inflammation provokes apoptosis and atrophy of the epithelial cells through the effect of pro-inflammatory cytokines and free radicals. Epithelial proliferation is a consequence of excessive apoptosis caused by the infection. It is stimulated by the expression of inducible cyclo-oxygenase and inducible nitric oxide synthase. The development of atrophic gastritis towards cancer is supported by nitric oxide which has a mutagenic effect on DNA and inhibits p53 protein and by the bacterium itself which decreases DNA mismatch repairing activity. The gastritis induced by Helicobacter pylori changes acid secretion according to the prevalent location of the gastritis in the antrum or in the gastric body. Prevalent gastritis in the gastric body causes hypochlorhydria by reducing the release of histamin from ECL cells and inhibiting the parietal cells through the effect of tumor necrosis factor and interleukin 1-beta. Hypochlorhydria is more marked among patients having a pro-inflammatory genotype for interleukin 1-beta and those infected by bacteria with virulence factors. In the event of antrum predominant gastritis, the pro-inflammatory cytokines cause a reduction of somatostatin and gastrin releases from the D and the G cells, respectively. The result of all is increased maximal acid output and the meal-stimulated acid secretion.
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PMID:[What are the gastric modifications induced by acute and chronic Helicobacter pylori infection?]. 1270 Apr 95

Cyclooxygenase-2 (COX-2) expression and certain growth hormones, such as gastrin, have been related to gastric carcinogenesis, but little is known about the factors that enhance this COX-2 expression and whether specific blockade of this enzyme has any influence on tumor growth and progression. Our objective was to determine the influence of a specific COX-2 inhibitor, rofecoxib (Vioxx), on serum and tumor levels of gastrin and its precursor, progastrin, as well as on tumor gene expression of COX-2, peroxisome proliferator-activated receptor gamma (PPARgamma), and apoptosis-related proteins (Bax and Bcl-2, caspase-3, and survivin). Twenty-four gastric cancer (GC) patients entered this study and were examined twice, once before and then following a 14-day treatment with Vioxx at a dose of 25 mg twice daily. For comparison, 48 age- and sex-matched healthy controls and 24 similarly matched Helicobacter pylori (Hp)-positive subjects were enrolled and treated with Vioxx as GC patients. Serum levels of anti-Hp and anti-CagA antibodies as well as IL-8 and TNF-alpha were measured by enzyme-linked immunosorbent assay (ELISA), while serum and tumor contents of progastrin and amidated gastrin were determined by specific RIA. Tumor gene and protein expressions of COX-2, PPARgamma, Bax and Bcl-2, caspase-3, and survivin were determined by RT-PCR and western blot. The overall Hp and CagA seropositivity in 24 GC patients was significantly higher (82% and 47%) than in 48 controls (61% and 22%) but not in 24 Hp-infected subjects (100% and 38%). Serum IL-8 and TNF-alpha values were significantly higher in GC patients than in controls without GC or Hp-infected controls. Median serum progastrin and gastrin levels were found to be significantly higher in GC than in controls without GC and in Hp-positive subjects. Treatment of GC patients with Vioxx resulted in a significant decrease in plasma and tumor contents of both progastrin and gastrin, and this was accompanied by the increment in tumor expression of COX-2, PPARy, Bax, and caspase-3 with a concomitant reduction in Bcl-2 and survivin expression. We conclude that: (1) GC patients show significantly higher Hp and CagA seropositivity than age- and sex-matched controls, but not Hp-positive subjects, indicating that infection with cytotoxic Hp is linked to GC. (2) Serum progastrin and gastrin levels are significantly higher in GC patients than in matched controls, confirming that both gastrins may be implicated in gastric carcinogenesis. (3) GC patients exhibit significantly higher levels of IL-8 and TNF-alpha than non-GC controls and Hp-positive subjects, probably reflecting more widespread gastritis in GC. (4) COX-2, PPARgamma, Bcl-2, and survivin were overexpressed in gastric tumor, but the inhibition of COX-2 activity by Vioxx resulted in a significant reduction in serum and tumor levels of progastrin and gastrin and serum IL-8 and TNF-alpha levels, suggesting that gastrin and proinflammatory cytokines could mediate the up-regulation of COX-2 in gastric cancerogenesis. (5) Vioxx also enhanced expression of COX-2, PPARy, Bax, and caspase-3, while inhibiting the expression of Bcl-2 and survivin, suggesting that COX-2 blockade might be useful in chemoprevention against gastric cancer possibly due to enhancement of the PPARy- and proapoptotic proteins-dependent apoptosis and the reduction in progastrin/gastrin-induced promotion of tumor growth.
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PMID:Influence of COX-2 inhibition by rofecoxib on serum and tumor progastrin and gastrin levels and expression of PPARgamma and apoptosis-related proteins in gastric cancer patients. 1462 49


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